Electronic timepiece

ABSTRACT

The operative components of an electronic timepiece are mounted side by said on a base plate in such a manner that any of the individual components can be separately removed without disturbing the other components.

United States Patent [191 Oki ELECTRONIC TIMEPIECE [75] Inventor: Toshihiko Oki, Suwa-shi,

, Nagano-ken, Japan [73] Assignee: Kabushiki Kaisha Suwa Seikosha,

Tokyo, Japan 22 Filed: Feb. 14, 1972 211 Appl. No: 226,077

[30] Foreign Application Priority Data Feb. 12, 1971 Japan 46-5580 [52] US. Cl. 58/23 TF, 58/53 [51] Int. Cl. G04c 3/00, G04b 37/00 [58] Field of Search 58/23, 23 BA, 23 TF, 28 R, 58/52, 53, 116 M [56] References Cited UNITED STATES PATENTS 3,628,323 12/197] Baumgarter 58/23 TF [451 Apr. 9, 1974 8/1972 Baumgartner et al 58/23 BA 9/1969 Naka et al 58/23 TF Primary Examiner-Richard B. Wilkinson Assistant Examiner-Edith Simmons Jackmon Attorney, Agent, or Firm-Blum, Moscovitz, Friedman & Kaplan [5 7] ABSTRACT The operative components of an electronic timepiece are mounted side by said on a base plate in such a manner that any of the individual components can be separately removed without disturbing the other components.

4 Claims, 2 Drawing Figures ELECTRONIC TIMEPIECE BACKGROUND OF THE INVENTION An electronic timepiece which indicates time by the usual hands, requires, as a minimum, an oscillator, electronic circuitry, a cell for powering said electronic circuitry and said oscillator, and a gear train coupled to the oscillator for controlling the time-indicating means of the timepiece. In conventional construction of such timepieces, it has been the practice that one or more components may overlie each other, so that removal of one component might require prior removal of others. Such a construction is relatively expensive with respect to repair when it becomes necessary to adjust or replace components, and similarly, the manufacture of electronic timepieces wherein components overlie each other imposes restrictions on the order of assembly and thereby increases the cost of such timepieces, especially in mass-production.

SUMMARY OF THE INVENTION In an electronic timepiece, the essential components, namely, an oscillator, electronic circuitry, a cell and a gear train are mounted on a base plate in non-overlying relationship so that any component can be removed from the base plate without disturbing the remaining components. A preferred oscillator is a tuning fork.

Accordingly, it is an object of the present invention to provide an improved electronic timepiece wherein the cost of manufacture and of repair is minimized by suitable arrangement of the components of the timepiece.

Another object of the present invention is to provide an improved electronic timepiece in which a gear train is driven by an oscillator.

A further object of the present invention is to provide an improved electronic timepiece driven by a tuning fork.

Yet another object of the present invention is to provide an improved electronic timepiece wherein a tuning fork is coupled to a gear train through a pawl or through a permanent magnet.

Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.

The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWING For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawing, in which:

FIG. 1 is a plan view of an electronic timepiece in accordance with the presentt invention; and

FIG. 2 is a plan view of another embodiment of an electronic timepiece in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An electronic timepiece in accordance with the present invention is shown in FIG. 1 in which tuning fork I serves to provide a fixed frequency. Tuning fork l is driven by coil 2 which in turn is supplied with electric pulses from circuit block 3. Power to circuit block 3 is supplied by cell 11. Coil 2 is part of a magnetic circuit which is completed by magnetic portions 4 engaged with tuning fork 1.

A pawl 5 transmits the vibration of tuning fork l to ratchet wheel 6. A second pawl 7 prevents reverse motion of the ratchet wheel 6. Intermediate gear 8 transmits rotation of ratchet wheel 6 to gear 9 and to a gear (not shown) on which is mounted a second hand. Gear 9 drives gear 10 which operates further time-indicating means such as minute and hour hands, and day and date wheels (not shown). The various wheels and gears constitute a gear train, the axes of which are mounted between base plate 12 and support plate 13.

The operative components of the electronic timepiece may then be considered to be the cell 11, the electronic circuitry 3, the magnetic circuit including magnet 2 and tuning fork l and the gear train driven by the tuning fork. As is evident from FIG. 1, no component overlies any other component. As a result, any

component may be individually removed from base plate 12 without disturbing the other components. Moreover, tuning fork 1 may be removed from coil 2 by removing screws 17 and sliding the tuning fork l in a direction parallel to its own tines. Similarly, by removal of plate 13, the gear train can be removed for repair or replacement. Finally, in the assembly of the electronic timepiece, the various components can be placed in position in any order as desired. These factors make for simple assembly in mass-production and for easy repair of defective timepieces.

The embodiment shown in FIG. 2 is similar to that in FIG. '1 except that tuning fork 14 has mounted thereon a permanent magnet 15 and wheel 16 is an escapement wheel made of a magnetic material which is engaged magnetically with magnet 15. The engagement between magnet 15 and escape wheel 16 is such that wheel 16 rotates in response to vibration of tuning fork 14.

As is evident from FIG. 2, the various components of the electric timepiece are mounted on the base 12 in the same order as in FIG. 1 except for the fact that magnet 15 and escapement wheel 16 replace ratchet wheel 6 and the two pawls 5 and 7.

The arrangement of components as shown in FIGS. 1 and 2 is such that the tuning fork is now positioned near the periphery of the timepiece. Heretofore, the tuning fork has been positioned in the center of the timepiece, whichh has made it necessary to use tuning forks of complex shape in order to avoid the gear train, much of which, of necessity, must also be placed near or at the center of the timepiece. As a result, such timepieces have been difficult to assemble and to repair. With the present arrangement, the anus of the tuning fork can be straight which makes it possible to manufacture the tuning fork in such a way that the arms coincide with the rolling direction of the stock from which the tuning fork is made. This provides the further advantage that ageing effects on the natural frequency of the tuning fork are minimized so that the timepiece retains its high accuracy.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above article without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

What is claimed is:

1. An electronic timepiece comprising a base plate and components including oscillating means having a characteristic frequency of vibration, electronic circuitry for driving said oscillating means, a cell for powering said circuitry and said oscillating means, a complete gear train for driving time indicating means, and

coupling means, said oscillating means driving said gear train through said coupling means, all of said components being mounted on said base plate in noninterfering relationship, so that any of said components may be individually removed from said base plate without requiring prior removal of any other of said components.

2. An electronic timepiece as defined in claim 1, wherein said oscillating means is a tuning fork.

3. An electronic timepiece as defined in claim 2, wherein said coupling means is a permanent magnet mounted on an arm of said tuning fork, and a magnetic escape wheel in said gear train.

4. An electronic timepiece as defined in claim 2, wherein said coupling means is a pawl mounted on an arm of said tuning fork and a ratchet wheel in said gear train. 

1. An electronic timepiece comprising a base plate and components including oscillating means having a characteristic frequency of vibration, electronic circuitry for driving said oscillating means, a cell for powering said circuitry and said oscillating means, a complete gear train for driving time indicating means, and coupling means, said oscillating means driving said gear train throuGh said coupling means, all of said components being mounted on said base plate in non-interfering relationship, so that any of said components may be individually removed from said base plate without requiring prior removal of any other of said components.
 2. An electronic timepiece as defined in claim 1, wherein said oscillating means is a tuning fork.
 3. An electronic timepiece as defined in claim 2, wherein said coupling means is a permanent magnet mounted on an arm of said tuning fork, and a magnetic escape wheel in said gear train.
 4. An electronic timepiece as defined in claim 2, wherein said coupling means is a pawl mounted on an arm of said tuning fork and a ratchet wheel in said gear train. 